Italy Tuesday, sending cars plunging nearly 300 feet to the ground and killing at least 11 people, officials said."

A section of a towering highway bridge collapsed in Italy Tuesday, sending cars plunging nearly 300 feet to the ground and killing at least 11 people, officials said.

The collapse of the Morandi Bridge in Genoa occurred during strong storms moving through the area of northwest Italy, according to authorities.

At least 20 vehicles were on the bridge in a port section of the city when the span gave way, Amalia Tedeschi, a firefighter, told the Italian news agency ANSA. Tedeschi said two people were pulled from the rubble alive and taken to a hospital by helicopter.

Danilo Toninelli, Italy's transport minister, described the collapse as "an enormous tragedy."

Several witnesses posted videos of the collapse on social media. In one video, someone can be heard screaming "oh God!" and a flash could be seen as the concrete structure crumbled.

The collapse happened on part of the viaduct on the A10 highway, the country's national police, Polizia di Stato, said.

Witnesses said the bridge toppled after it was struck by lightning.

Italian authorities said that at the time of the collapse construction was occurring on the bridge and a crane was being used on the span, but it was too early to pinpoint what caused the bridge to fail.

The A10 highway, the main route between northern Italy and France, was closed in both directions as search-and-rescue teams searched for survivors of the horrific incident.

Italian Interior Minister Matteo Salvini said about 200 firefighters were on scene searching for survivors.

Part of the bridge fell on top of the Genoa Garbage Collection Depot, raising fears that the death toll will climb.

Italian Prime Minister Giuseppe Conte was traveling to the scene, officials said.

The Morandi Bridge, which opened in 1967, is about a half-mile long.

Alaska's North Slope was hit Sunday by the most powerful earthquake ever recorded in the region, the state's seismologist says. At 6:58am Sunday, the magnitude 6.4 earthquake struck an area 42 miles east of Kavik River Camp and 343 miles northeast of Fairbanks, the state's second-biggest city, the AP reports. The US Geological Survey says the earthquake had a depth of about 6 miles. State seismologist Mike West tells the Anchorage Daily News that the earthquake was the biggest recorded in the North Slope by a substantial amount. "This is a very significant event that will take us some time to understand," he says.

The previous most powerful quake in the North Slope was in 1995 at magnitude 5.2, West says. The jump from a 5.2 to Sunday's 6.4 is significant because earthquakes rapidly grow in strength as magnitude rises, he says. A magnitude 6.4 earthquake is 15.8 times bigger and 63.1 times stronger than a 5.2 earthquake, according to the US Geological Survey. "That's why at 6.4 this changes how we think about the region," West says "It's a little early to say how, but it's safe to say this earthquake will cause a re-evaluation of the seismic potential of that area." Later Sunday, another magnitude 6.1 earthquake hit at 1:15pm near the city of Kaktovik on Alaska's North Slope, the US Geological Survey says.